sravan/system76-edk2
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

ArmPkg: Add comments to ArmEnableVFP

Browse Source 
git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@11740 6f19259b-4bc3-4df7-8a09-765794883524
This commit is contained in:
oliviermartin
2011-06-03 09:25:51 +00:00
parent f0fef790ff
commit 4705b7da4b
2 changed files with 14 additions and 8 deletions
Download Patch File Download Diff File Expand all files Collapse all files

11
ArmPkg/Library/ArmLib/ArmV7/ArmV7Support.asm
View File

@@ -314,12 +314,15 @@ ArmWriteCPACR
bx lr
ArmEnableVFP
// Enable VFP registers
// Read CPACR (Coprocessor Access Control Register)
mrc p15, 0, r0, c1, c0, 2
orr r0, r0, #0x00f00000 // Enable VPF access (V* instructions)
// Enable VPF access (Full Access to CP10, CP11) (V* instructions)
orr r0, r0, #0x00f00000
// Write back CPACR (Coprocessor Access Control Register)
mcr p15, 0, r0, c1, c0, 2
mov r0, #0x40000000 // Set EN bit in FPEXC
mcr p10,#0x7,r0,c8,c0,#0 // msr FPEXC,r0 in ARM assembly
// Set EN bit in FPEXC. The Advanced SIMD and VFP extensions are enabled and operate normally.
mov r0, #0x40000000
mcr p10,#0x7,r0,c8,c0,#0
bx lr
ArmCallWFI